Eriogonum incanum

Torrey & A. Gray

Proc. Amer. Acad. Arts 8: 161. 1870.

Common names: Frosted wild buckwheat
Endemic
Synonyms: Eriogonum marifolium var. incanum (Torrey & A. Gray) M. E. Jones Eriogonum ursinum var. rosulatum (Small) S. Stokes
Treatment appears in FNA Volume 5. Treatment on page 366. Mentioned on page 335, 365, 367.

Herbs, matted, dioecious, 0.5–3 × 1–4 dm wide, tomentose to floccose. Stems: caudex spreading; aerial flowering stems erect or nearly so, slender, solid, not fistulose, arising at nodes of caudex branches and at distal nodes of short, nonflowering aerial branches, 0.1–2(–2.5) dm, tomentose to floccose. Leaves in loose to congested basal rosettes; petiole (0.3–)0.5–1 cm, tomentose; blade oblong to oblong-ovate or spatulate, 0.5–1.5 × 0.3–0.7 cm, densely white- or grayish-tomentose on both surfaces, sometimes greenish adaxially, margins entire, plane. Inflorescences capitate and 0.5–2 cm wide, mature pistillate plants open and umbellate, 1–3 × 1–4 cm; branches tomentose to floccose; bracts 2–6, leaflike, 0.1–0.5 × 0.1–0.3 cm, often absent immediately below involucre. Involucres 1 per node but occasionally appearing congested, turbinate-campanulate, 2.5–3 × 2–2.5 mm, tomentose; teeth 5–8, erect, 0.5–1 mm. Flowers stipelike base 0.5–1 mm; perianth yellow, glabrous; staminate flowers 2–3 mm, tepals ovate; pistillate flowers 4–6 mm, tepals oblanceolate, often becoming reddish in fruit; stamens exserted, 2–3 mm; filaments pilose proximally. Achenes light brown to brown, 3–3.5 mm, glabrous except for sparsely pubescent beak.


Phenology: Flowering Jun–Sep.
Habitat: Sandy to gravelly or rocky granitic or occasionally volcanic flats, slopes, and outcrops, mixed grassland, manzanita, and sagebrush communities, montane conifer woodlands
Elevation: (1900-) 2100-4000 m

Discussion

Eriogonum incanum is common throughout the central and southern Sierra Nevada of California (Alpine, El Dorado, Fresno, Inyo, Madera, Mariposa, Nevada, Tulare, and Tuolumne counties) and extreme west-central Nevada (Carson City, Douglas, and Washoe counties). It is a food plant for the green hairstreak butterfly (Callophrys lemberti), the Pacific dotted-blue (Euphilotes enoptes), and the gorgon copper (Gaeides gorgon).

Selected References

None.

Lower Taxa

None.
... more about "Eriogonum incanum"
James L. Reveal +
Torrey & A. Gray +
Frosted wild buckwheat +
Calif. +  and Nev. +
(1900-) 2100-4000 m +
Sandy to gravelly or rocky granitic or occasionally volcanic flats, slopes, and outcrops, mixed grassland, manzanita, and sagebrush communities, montane conifer woodlands +
Flowering Jun–Sep. +
Proc. Amer. Acad. Arts +
Eriogonum marifolium var. incanum +  and Eriogonum ursinum var. rosulatum +
Eriogonum incanum +
Eriogonum subg. Oligogonum +
species +